Philips 107T60 Service Manual page 53

BRIEF CIRCUIT DESCRIPTION
GENERAL DESCRIPTION
V32 107T5, using 17 flat High Brightness CRT, are so-called
with high resolution which can operate at horizontal scan frequency from 30KHz up to 71KHz, and vertical scan
frequencies from 50 to 160 Hz. It adopts a brand new Demic IC
Deflection and Micro-controller in one chip with 56 pins.
The monitor is equipped with an embedded micro-controller (included in Demic IC), which can preset the required
modes. It also provides many functions, such as digital adjustable picture, DDC2B, power management, sRGB, low
emission, high immunity, ---- etc.
The monitor complies with TCO99/TCO 03/MPRII low emission standard and also fulfill E2000 automatic power
saving requirements, to reduce power consumption to less than 1 watts in power saving mode. The monitor also
complies with VESA standard and energy star computer program initiated by the EPA.
1. DESCRIPTION OF CIRCUIT DIAGRAM
This description mainly introduces the functions including power supply, power saving management, horizontal /
vertical deflection, video amplifier, and micro-controller, etc.
A. POWER SUPPLY / POWER SAVING MANAGEMENT
The monitor is designed to adopt switching mode power supply which can operate mains input from 90VAC to 264VAC.
This switching power supply applies an IC TEA1507. The control scheme transforms a rectified voltage source into a
multi-output voltages. The control concept exhibits many desirable properties such as inherent over-load protection,
stable and fast system response. A current sense circuit (R3107/08/09, etc) is equipped for power limiting (90W) and
safety reason on primary power supply circuit. Secondary feedback via a photo-coupler is used to obtain a stable
output voltages. The secondary outputs supply all necessary voltages for deflection and video and micro-controller.
Power transformer and peripheral ckt are same as 107T5. The main differences are 7153, which has been changed
from L78L05ACZ in TO92 package to L7805CV in TO220 package, and 7151, which has been changed from BC338
to BC638, due to the larger load of +5V line because of the use of Demic IC which is supplied +5V.
All rectified diodes on secondary site are without lead frame ( heat-sink), it gains some cost saving in thermal design,
but the turn ratios of main transformer should be well determined to maintain an adequate voltage derating of
primary switching MOSFET and secondary +190V rectified diode BYV26E (with better thermal performance).This is
trade-off design in between. The other hand, a secondary DC power switch (tact sw) is adopted. And B+190V
adjustment is not needed. A fixed resistor (3162), same as 107T5, is still used..
This monitor can save power consumption while no sync pulses and automatically recover to normal power-on when
sync signals are detected by micro-controller. The power saving off mode still exists in new designed monitors, but
suspend / stand-by mode are deleted due to patent infringement issue.
During Off mode, LED will flash and all the output voltages of main power are reduced to a very low level, and the
operating frequency also comes very low, and only the required voltage of Demic IC (+5V) is supplied. When the
monitor is switched off it is actually in burst mode (< 1W).
1 inch 7
TYPE
BRAND : PHILIPS
2004-04-19
CRT Monitor
:107T60/00
2004-04-19
Digital Controlled Auto-scan Color Display Monitor
SAA4848, made by Philips, which incorporates
8639 000 15483
4 2
107T6 CRT
53
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